Question Of The Day

What is the mechanism by which Leucovorin increases the cytotoxicity of 5-fluorouracil (5-FU)? Thymidylate synthase is an enzyme necessary for DNA synthesis that is inhibited by a 5-FU metabolite, fluorodeoxyuridine monophosphate (5-FdUMP). A leucovorin metabolite, (6R)-5,10-methylene-THF, stabilizes the complex of 5-FdUMP and thymidylate synthase, leading…

Historical QOD 2/3/2009: What is the fractional conversion of cocaine to cocaethylene in the presence of substantial blood ethanol concentrations? Approximately 17 % if cocaineis converted to cocethylene in the presence of presence of substantial blood ethanol concentrations. Harris DS, et al. 2003. Drug and…

In a study of sexual minority men (from the PrEP and Substance Use National Survey 2020), was a strong sense of ethnic identity as Black associated with more or less substance use in this sample? Although the experience of racism and stigma related to sexual…

What is the most common adverse event reported after an acute amiodarone overdose? QTc prolongation has been reported in several cases. Tetsuhiro Takei, Hiroko Fukushima, Junji Hatakeyama, Michiko Fujisawa & Toshitaka Ito (2011) Acute amiodarone poisoning occurring twice in the same subject, Clinical Toxicology, 49:10,…

What secondary toxins are formed when carbon tetrachloride is used to extinguish a fire? Phosgene or COCl if formed when carbon tetrachloride (CCl4) is used to extinguish fires Hamilton A (1933) Formation of phosgene in thermal decomposition of carbon tetrachloride. Industrial & Engineering Chemistry 25(5),…

During the 1918–1919 influenza pandemic, the surgeon general recommended a treatment for the infection that may have led to toxicity and an increase in the mortality. What was the recommended treatment? Salicylate toxicity may have been responsible for some deaths, as the findings on autopsy…

Historical QOD 2/2/2009: What does the “n” in n-hexane stand for? The “n” stands for “normal” to distinguish it from the isoforms of hexane, 3-methyl pentane, 2-methy pentane and 2,3 methyl butane. Dick FD. Solvent neurotoxicity, 2006, Occ Env Med, 63:221-226

In a nationwide, sociodemographically diverse, prospective longitudinal sample of U.S. youth in early adolescence (N = 7,842), how did alcohol use change over the first 6 months since COVID-19 stay-at-home orders were first issued in the U.S.? Fewer young adolescents were using alcohol during this…

In a retrospective study of 26 patients with a therapeutic valproic acid (VPA) concentration, what percentage decrease in the concentration occurred after the administration of meropenem? There was a decrease in VPA concentrations of 67%±19% after the administration of meropenem. Wu CC, Pai TY, Hsiao…

Are college students diagnosed with an eating disorder more or less likely to report substance abuse than their peers? 414,299 students’ responses to the National College Health Assessment (conducted by the American College Health Association) between 2015 and 2019 were examined. Students with an eating…